my parents ()at home.a.are both b.are all c.all are d.both are

问题描述:

my parents ()at home.a.are both b.are all c.all are d.both are
请问为什么选a,bc中有all错哪.be动词放哪

both和all都是“都”的意思,但是all是三人以上时使用,两人时用both